1. Field of the Invention
The present invention relates to protection from ultraviolet radiation, and particularly to an ultraviolet shielding compound that is highly transparent in the visible light spectrum and provides a shield against approximately 100% of ultraviolet A (UVA), ultraviolet B (UVB) and ultraviolet C (UVC) radiation.
2. Description of the Related Art
Ultraviolet (UV) light is ionizing radiation having a wavelength spectrum between 180 and 400 nm. The ultraviolet spectrum is commonly divided into the following three regions, including the ultraviolet A (UVA or “black light”), which has a wavelength range between 315 and 400 nm; ultraviolet B (UVB or erythemal), which has a range between 280 and 314 nm; and ultraviolet C (UVC or germicidal), which has a wavelength range between 180 and 280 nm.
Environmental exposure to ultraviolet radiation is typically limited to the UVA region as a result of exposure to direct sunlight. The Earth's atmosphere shields most of the more harmful UVC radiation, and more than 99% of UVB radiation. However, some equipment can generate concentrated UV radiation in all of the spectral regions that, if used without the appropriate shielding and personal protective equipment, can cause injury with only a few seconds of exposure.
An unfortunate property of UV radiation is that there are no immediate warning symptoms to indicate overexposure. Symptoms of overexposure, including varying degrees of erythema (i.e., sunburn) or photokeratitis (i.e., “welder's flash”) typically appear hours after exposure has occurred. In humans, prolonged exposure to solar UV radiation may result in acute and chronic health effects of the skin, eye, and immune system. UVC rays are the highest energy and, thus, are the most dangerous type of ultraviolet light. Little attention has been given to UVC rays in the past, since they are filtered out by the atmosphere. However, their use in equipment such as pond sterilization units may pose an exposure risk if the lamp is switched on outside of its enclosed pond sterilization unit.
Thus, an ultraviolet shielding compound solving the aforementioned problems is desired.